Connector switch controlled from either calling or called party to transmit different types of signaling



Patented Feb. 14, i950 UNITED N,sinistres CONNECTGR SWITCH CONTROLLED FROM EITHER CALLING 0R CALLED PARTY T0 TRANSMIT DIFFERENT TYPES OF SIG- `Clarence Lomax, Chicago, Ill., assignor to ,AutomaticElectrie Laboratories, Inc., Chicago, Ill., a corporation of Delaware Application September 151945,"Serial No. 616,616

` '25 Claims. l

This invention relates to :telephone systems in :general but more particularly to automatic syslto indicate to a stafimember by the type of .ringing signal which .he 4hea-rs on the ringerrof his telephone, that he is being .called by said oilicial `or executive.

AAnother object of this invention is the control of facilities for informing, by a suitable wanted signal, subscribers who are engaged on :a connection that a connection -to their line is desired bya superior oiiicer or a more important :call is waiting, such as a toll or long distance `call, which should be given preference over a local call.

Another object of this invention is the control of various types of ringing facilities which .are provided to give to called lines a ringing signal in accordance with ythe terminal arrangement of said lines and means ,for cancelling out the ycontrol by said terminal arrangement When the call is originated by. a specific class of subscriber yand substituting other means for the control of `the ringing signal.

Another object of this invention is to arrange `the telephone lines in groups, or on specific lev' els of the selecting switch, in such afmanner that one group of lines will receive one type of ring- .ing signal and another group will receive a diferent type of ringing signal.

Another object of this invention is `to providefi in a connector switch circuit,va pick-up-relay which prevents a partial code or ringing signal from reaching the called line. The relay allows .the ringingcurrent to be connected to the calledy `.line only at `the commencement of a code 4so that" only a complete code can be transmitted to the called line.

The above objects and othersare accomplished by providing new and simple features in the formMi- The control of the wanted signal .is Aaccomplished by providing a relay which can operate in series with, or in/multiple with, the busy relay and is controlled by a call from an executives line but not controlled by calls from, vso called, ordinary subscribers lines.

By arranging the lines in groups on the connector bank contacts, such vas even and odd levcls, or other groupings, the type of ringing signal is controlled by providing shaft springs which will operate on particular levels or 4in relation to certain bank contacts or groups of bank contacts, on a specified level or levels.

An instance of the advantages to be gained `by the provision of some of the above mentioned features, would be in a large organization where it is necessary for the manager, or other executives, Ito frequently converse over the telephone with his staff members. The manager calls the number of the .party with .Whom he wishes to speak and nds Athe line engaged. The calling executive will receive the regular busy signal and .at the same time a distinct wanted signal will be transmitted to the wanted subscribers line and the stall? member will know that an executive is calling. `The staff member will y.hang up his receiver to clear his line after which the connector switch will complete the connection and ring the bell of the stall? members telephone. The executive who has been camping on the previously busy line may now converse with his staii member with practically nofloss of time and withoutbeing compelled to make a second call.

of additions or alterations to Well known types of automatic switches, also variations in bank terminal .arrangements and ringing interrupter leads.

Certain advantages or .objects .are obtained by... providing 4in the .circuit of the well known com" nestor, a relay which will be controlled either .from the individual trunk .selecting switch ol specific classes of calling subscribers, such .as

executives lines, or by the terminals oi the called..

When this relay `is controlled by a call" originated by an cxecutives line, thesaid ter- .minalfacilitiesof the called line forcontrolling the type .of ringing-signal, .are renderedineiiective and the controlis from the ,callinglline.

line.

The invention in the speciiic formichosen for `this illustration of the control of the ringing signal herein contemplates a ,relay in a connector circuit which may be operated from a calling executives line or from the terminal of the called .-line, this relay governs the typelof ringing signal which will be given to the called line. Another relay is used to .accomplish the feature of yvvantecl signa and camp-on-busy.

Theobjects and features will be clearly understood 'from'a perusal of the drawings, whiohconsists of 5 figures on .l sheet.

Figurel is the lcirouit'oi an ordinaryfconneotor but .having xanovel ringing signal control relay and a second rela'y'for `the control v.of the wanted :wsignal `and camp-on-busyfeature.

Figure 2 shows an additional relay which can 'be included in this Vconnector circuit to 4provide Ia pick-up `feature to operate in connection with 'the ringing control relay.

Figure 3 shows 'a 'modiiied `form of the ringing signal control feature o this connector circuit v'vvl'ierein shaft controlledsprings are used.

Figure 4 shows a modied form of the ringing control 'feature voi `this connector circuit wherein the ringing signalimay be 'controlled by 'current 3 on a control bank contact associated with the line bank contacts of the called line.

Figure 5 shows another modication of this connector circuit to provide for the control ci the wanted signal relay operating in multiple with the busy relay.

Referring now to the drawings, Figure l is a circuit of a connector of the well known type which responds to impulses from a calling dial to move its shaft and wipers vertically one to ten steps and one to ten steps horizontally to connect its incoming conductors |20 and |2I to the lines of the wanted subscriber. The two conductors of a calling subscribers line, after entering the telephone ofce, are connected to an individual trunk selecting switch and may pass through one or more selector stages before reaching the connector of this invention. These switching stages and the switches involved therein are well known and therefore are not shown herein. It is sufficient to note that conductors |123 and |2I are connected to the calling station, and the impulses for building up the call, as well as the conversation takes place over this pair of conductors. Conductor |22 is the Well known private conductor or holding conductor and conductor |23 is a special service conductor from the aforesaid individual trunk selecting switch through the one or more selecting stages, if there are selectors in the system, to relay 30 in the connector. In this invention conductor |23 is not brought into use when a call reaches this connector from an ordinary subscribers line, however when a call originates at the station of a special class of subscriber, such as an executive, a ground (positive battery) is placed on this conductor |23 by the individual trunk selecting switch. This conductor |23, known as the executive control lead, passes through contact 24 on relay 20 to the Winding of relay 30, therefore relay 30 Will operate after relay 2|) operates, on all calls from the lines of executives, or from special manual switchboards, such as toll or long distance boards, but will not operate when the connector is seized by an ordinary subscribers line.

Having briefly described the invention as shown in the drawings, a detailed description of the operation will now be given.

For the rst description we will assume that the subscriber who has made a call and Whose telephone and line are now connected to conductors IZLI and I2I, is a so called ordinary subscriber. In this instance conductor |23 is not furnished with positive battery. The receiver and transmitter in series with the dial impulse springs are across the conductors I 20 and I2|, relay I5 operates and at contact I6 closes a circuit to operate relay 2D, relay 2o operates and through contact 23 connects ground back over the private conductor |22, through the one or more selector stages, if there are selectors in the system, to the individual trunk selecting switch (not shown) associated with the calling line to hold the said selecting switch in its operated position. Contact 24 on relay 2li is also closed but has no elect because n potential is present on conductor |23. Contact i9 on relay 20 is also closed to furnish a ground to a part of the locking circuit of relay 8|! also to contact 6I on relay 6|) which, as explained later, furnishes ground for the operation of the busy relay 60.

Contact 23, on relay 2li, in addition to grounding the control conductor |22 to hold the individual trunk selecting switch, and other switches if any 4 be in the circuit, furnishes ground through contact 29 of the vertical off normal spring combination to operate relay 25, relay 25 closes contact 28, but this has no eifect at the moment as the circuit is open at contact I1. The calling subscriber now operates his dial, opening and closing the circuit of relay I in accordance with the digits of the called number. Armature I8 of relay I5 will follow the impulses from the dial and from ground through contacts Il, 2| and 26 will repeat these impulses to the vertical magnet 28 causing the shaft of this connector to be raised a number of steps in accordance with the number of impulses. Relays 20 and 25, being slow releasing, remain operated during the series of impulses. When armature I8 comes to rest operated, after the first series of impulses, relay 20 is again connected to ground through contact I6 and remains in operated position. Relay 25 however, restores to normal shortly after the complete series of impulses have been received into relay I5, and as Contact 29 is now open due to the shaft being on normal, relay 25 restores, switching the impulsing circuit from the vertical to the rotary magnet 9| and relay 1D. The second series of impulses will be received into the rotary magnet 3| and relay 10 in multiple. The rotary magnet 9| will cause the shaft to be rotated horizontally and relay 'I0 being slow releasing, will operate and remain operated throughout this second series of impulses. Relay 10 holds control conductor |42 connected through contact 13 to busy relay 5l] and at the end of the series of impulses control wire |42 will be connected with the control 'wire of the wanted line. Should the called line be engaged, its control Wire (not shown) will furnish ground to control wire Ill-2 and through contact i3 on relay 10, which remains operated for a short time after the series of impulses which operated the rotary magnets, to busy relay 58. The busy relay Will operate, closing its contact 54 to connect the busy tone lead 66 through condenser 64 and condenser I3 to positive line IZil, thus giving the busy signal to the calling subscriber. It should be noted at this point that the operation of relay 5|), which takes place as soon as conductor |42 connects with ground on the control wire of the called busy line, closes a circuit at contact 52 which connects ground from contact I9, through 6l, 52, 33 and contact 12 to relay 50 which forms a locking circuit preventing relay 50 from restoring and continuing to hold the busy tone on to the calling line, and this circuit will remain in this condition until released by the calling subscriber hanging up his receiver. It can be noted at this juncture that the winding of relay is shunted by contact 33 and therefore does not operate at this time.

Now assuming that the called lines was not engaged at the moment conductor |42 connected with the control conductor of the called line, relay 50 would not be energized and as relay 'lll would restore a short time after the last impulse of the series, control conductor |42 would be connected to one winding of relay 8|] through contacts 14 and 86. 'Relay 80 operates over the following circuit: battery, through a relay (not shown) connected to the control lead of the called line, control lead |42 through contacts 'I4 and 86, through one winding of relay 80, contacts 53, 6I and I 9 to ground, closing its contacts BI, 85, 31, 88, 89 and 9,0 and opening contacts 82, 83, 84 and 86. Contact 85 is part of a locking circuit and relay will remain in operated position until -phone (not shown) is -acrossthe conductors L|14! tact 45, condenser I4 'to conductor |2| andtothe .switch (not shown) `of the called line over lead contact |9 on rrelay '20 is opened, that is,.;fa!ter the calling Subscriber hangs 11p his receiver. 'Itis is associated `with Va called line, and `these con- `-l x tacts will be furnishedwith various-types foi in terrupted ground rfrom an interrupter `machina-a indicated. Eachtime ground is supplied Vbythe interrupter machine vto conductor |48 "through contactspl and 4| and through relay V3|| toba'te tery, relay 30 willoperate, closing the 'ringing cir..- cuit fromthe direct generator lead 35 through contact 32, one winding ofrelay 49, contacts .M land 89 Vto conductor -|4|. As the called -tele and I4 I, the'ringing `circuit Will'pass throughfconductor I4 I, the telephone ringer and itsv condenser, conductor 40, contact 88 'to yground lat lcontact 44. Thus the type of 'ringing `signal :given to the ringer of the called'number will be depeiid- ,q ent upon the type of `ringing interrupterwhichfis chosen for connection vto the terminals :of the called line. Contact 90 `of relay 8u connectsrtlie ring-back tone lead lthrough condenser", con"- vcalling subscribers telephone to advise the calling subscriber of the progress of his call.

Now, assuming that the calling party isan executive and that his telephone and `line have *been connected through his individual trunk selecting switch (not shown) to conductors INI-anti I2 I. At the same time the control conductor from 4the individual selecting switch has beenoonnectq ed through the conductor `|22 and, in lthis in,- stance the executive controlconductor |23 is=noiw `connected tolground at the selecting switch.

before, relay I5 operates and closesvcontact *|36 to operate relay 20, relay `2|) through contact .24 closes thecircuit to `operate relay 30. This ,relay 30 will remain operated for -the'durationof the connection and lit will l'be noted that regardless vof any ground or interrupted ground condition on the conductor "|43 after the vcalleolline has :been selected, it will have no effectr on relay'30. Inthis manner, Ithe control of relay 30, by the --special conditions of the terminals oi the calling vline cause the control bythe terminal facilities of `the ycalled line, which control 1the type oi ringing` signal to be vgiven to the called line, tobe rendered ineffective and a diierent rtype of ringing signal to be given. The executiveproceeds with the call inztheusual manner and assuming'that the called line is not 4engaged when'the last digit :has-:been

idialed, `battery from the individual trunk Yselecting |42 will `operateirelay 80, closing the `line circuit |40 and I4| at contacts `8|! and89 over ywhich the ringing signal will begivemfrom direct'generator lead 35, Contact 32, onewinding of relay 40,.con ytacts '41 and A89, conductorv l-4I, ythrough thelitne and telephone of the `called-party, conductor it, contacts B8 and y44 to ground. ,The Continuous ringing signal Will immediatelyindicate to #the `called subscriber that the calling party Ais'aneexvecutive who requires prompt attention.

Should the line, which has been soalflediby Vthe f executive, vbe Aengaged :at the .moment conducta: |42 is connected to .the control conductor ofthe called line, `ground from `the individual ltflii'nr'ik selecting switch, over |42 will operate :relay zl and as soon as the slow1releasing relay 'lxdrops back after the lastdialed digit, contact 'I.2 ;onrre lay 'III will close. completinggacircuit, v,dufextotlie 'wimagnet y:and relay 19 in fmultiple.

zfoilowsz'battery, of relay4v l50,':contact '12. windingtofifrelayfjcontacts 52, 6I and1|9 `to ground. Asisoonfasithemake-be'fore-breakspring fcombinationsfonirelayf has'foperated, a holdsing groundafor 4 relays 50 and 60 is obtained from conductorV 'I 42 fandj these relays arelno longer unider the "control of the ground connection atcon- `tact |9onwre1ay 20, 'thereforethe release of revlays Staand i0 lwill now depend on the 'freeing Iofthe called line. operation of relay 6U, ex- `gpiainedabove,'closecloneoi its contacts63 to con- Yneet la special wanted signal lead 48 through condenser 165, -;contact c83 zto conductor |4I. A1- though'i'.hecalled partys line isvengaged, the dis- -gtinctive lvwanted'itone signal can be heard and the `ibusy :subscriber will "know that an executive is Yrwanting.toestablish aconnectionandtherefore he will-res`torefhis receveritofree his line. The 'free- "fingof-.theycalled line `will `cause the ground potenfstial to beremovedffrom vcontrol conductor |42, which Iallows relays 150 andiil) to restore Aand anl.nthericircuit is established, as follows: battery ytltlnough a vrelay :iin fthe-.individual trunk selecting switch'over'conductor |42, contacts "I4 and 86, @one .windingfof'relayl contacts 53,'6I and I9 to ground, :operating'relayfl `Now the same condi- "ltions :prevail `as when :an executive calls a line .iwhichiisnotengaged,as previously explained and there'forefthe'executive's 4ca'llfrom this point onn ward willlproceed in `,the usual way. The called fsubscriberrs bell will receive a continuous ring -fandhe millanswer immediately,resulting in practically ,no viielayfto `'the executive although the :line `hecalledwas engaged'atfthe moment he'iirst established'ftheconnection.

",[twa.s"x1o|',exl in the-explanation `above that re- .layzmperated in series with relay 50, however fthe samefunctionsmay be accomplished by con'- necting relayzitoabattery through a suitable re"- .listlnwuchasfBTinLFgure 4V5 and operating it in .multlplewlthzrelay 50. 'In this arrangement -dueztofpossibleoperation of relay 60 when passing :busy :contacts relay `1l) is-provided with a Contact .'15 as shonwniin Figuren whichremains open dur- .dng the pperation ofthe rotary magnet and therezfore '.assureszthatithe wanted signal will not be k.minimunicatedte lead I4| `:until the `slow releasrelay 1I) lhas `restored, that is, a short time `:vuiteritlie last impulse :which operated the rotary In other re-l fspects the:explanation1is the `same as previously 18h68.

"Tojlvrwide-forthe pick-up feature, one relay is lifurnished-,in'addltion topthoseshown in Figure 1.

llhisgrelagy,12|9zis wiredfinto the circuit as shown Vcaneffectivedue.to the fact `that the pick-up circuit ,-.wilLbe open :atfcontact 36 nn relay 30. This conitact 36 will be lopenedfasfsoonas the call from the vexecutives'linevlms been advanced to the conrnectorofthiginventionzandrelays' I5, 20 and 30 ce kavefopersted y:andthe `circuit will remain open :while @this connector fis `.used by a-n Vexecutive's Jine. llt willbefrememberedirom'the above ex- ;gplanationfthat `a calljrom `an executives line "eauseszirelay .l0 .totoperate -to cause a continuous ,170 ming to `be -sent @to thecalledline, therefore the pick-up fservicewis not required.

,-LIHowever. when a "call is `made lcyan ordinary rssubscriberslineandtheterminalfacilities of the ,esuediinefareituemeansior determining-:therme :operation `ci :relay .B0 in :series aerith-galas'- limsf* fictrinsing-z,igualitzofixie'igiirenL the called line, .than

mames the pick-up feature is available to assure that a. part of a ringing signal, forexample, a part of a coded signal, will not be sent tothe called line- The operation is as follows: an impulse of ground battery is applied to the pick-up lead .-2-|5 between each two code signals, by the'ringing and ringing interrupter machine (not shown) and this impulse of current serves to operate relay 2|0, prior to which the interrupted ground from one of the contacts 19, in Figure l, over lead |43 cannot operate relay 30 to start the ring, due to the circuit being open at contact 2|3. We will assume that the last impulse of the dialed number has caused leads |40, |4|, |42 and |43 to be connected to the terminals of. the called line, and that line is not engaged. This means that bat,-V tery from the individual trunk selecting switch of the called line is connected over lead |42, which as explained above would serve tooperate relay 80 and close a part of the ringing circuit.` In this instance however the circuit to relay 30 is open at contact 2|3 on relay 2|0 and this relay must have an impulse of current over lead 2|5 before it can operate. Once operated it locks through one of the contacts 2|2, to the control conductor- |42 and therefore will remain Y. operated during the period of the connection. The impulse of current over lead 2|5, through contact 2|4, on relay 8|) which is now operated, contacts 36 and 2| and the winding of relay 2|!) to'battery, will Y operate this relay and, as previously stated, will lock through contact 2|2 to a groundconnection on lead |42. As soon as relay 2||l operates, con'- tact 2| 3 is closed completing thecircuit to one winding of relay 30, which relay will now respond to whatever conditions are imposed by the facilities at the terminals of the called line over the lead |43, and the type of ringing signal will be in accordance with said facilities. v

Figure 3 illustrates a modiedform of the in'- vention shown in Figure 1, showing a method of f giving to .the ringers of called lines, one of three types of ringing signal, that is, comparatively short intermittent or comparatively long intermittent or a continuous ring. It is explained as follows: when a calloriginates at the station of an executive, lead |23 as previously explained, will receive ground from the individual trunk selecting switch and the seizure of the line will operate relay 20 k(in Figure 3), to close contact 24, whereby the. ground on lead |23 will operate 'I relay 30. Relay 3|l operates to open contact 33| and close contact 32 which will connect continuous ringing lead 35 through one winding of ringing relay 40,' as previously explained, to the called line, so that a call from an executives sta- '"f" tion will causea continuousring on the ringer of the called number. However, when the call originates at anordinary station, relay 30 does not operate and the control of the type of ringing signal to be'given the calledlineis by the shaft springs, that is springs which will be operated by the shaft during its vertical or rotary movement. For example, if the tens digit in the called number isv an odd figure, shaft spring 332 will no-t be operated and therefore the intermittent short rings ff'rom the ringing machine (not shown) will be received into this connector over lead 335, throughlcontaci'.I 333, via spring 332, contact 33|, one'winding of ringing relay 40 to the called subscribers line, as previously explained. Again, when the tens digit in the called number is an even'gure, which means that the shaft would rise tmone of the evenl levels, shaft 'spring 332 Willb el moved to the rightflinl-Fi-g- Iure 3) contact 333 will open and contact 334 will close. Thus the type of ringing signal which would be given to a. called line on an even num'- bered level, would be a comparatively long intermittent ring from ringing lead 336 via contacts 334 and 33|, through one winding of relay 40 to the called subscribers line in the usual manner. It will be noted by reference to Figure 3 that relay 3U is completely under control of that class of calling line, for instance an executives line, in which the individual trunk selecting switch places ground on lead |23, which may be termed the executive control lead. The ring control relay 30 is therefore equipped with a single winding in v15 the circuit in Figure 3, instead of two windings, as shown in Figures 1 and 2. Should a connector, using the wiring as per Figure 3, be seized by an ordinary subscribers line, no ground would be placed on lead |23 by the individual trunk selecting switch, nor would the terminals of the called line determine the type of ringing signal to be sentA to the called line, the type of ringing 4signal being entirely controlled by the number ofthe-level to which the called line is connected. The terminals of the lines can be grouped in numerous ways and one group supplied with a comparatively short ring, while another group would be supplied with a comparatively long intermittent ring.

Figure 4 shows another form of control of the type of ringing signal by the terminals of the called line. It will be seen that in this arrangement after the last digit has been dialed and the wipers of the connector switch are resting on the A35 terminals of the called line, lead |43 would be lconnected with one of the ringing signal control contacts 4| 3, 4|4 or 4|5. The wiper control relay 80 operates in the usual manner to connect the calling and called lines together as illustrated in Figure 1 and described above. The operation of relay 80 closes contact 8| which connects lead |43 to the winding of relay 3D. When there is no ground on the ringing signal control contact corresponding to the dialed number, such as 4|3 and 4| 5, relay y,3(1 will not operate and the called line will receive yringing current from ringing lead 335 which is a comparatively short intermittent ring. However, when the ringing signal control contact of the 5 0 called line is grounded, such as contact 4 |4, relay 30 will energize through contact 8| on relay 80.

Relay 30 operates, closes its contact 4 2, thus connecting ringing lead 336, through one winding of the ringing relay 40, to the called line and said 55 line will receive a relatively long intermittent ring. Other features of providing busy signal, ring-back-tone, etc., are the same as described above in connection with Figure 1.

Having described my invention, what I consider 60 to be new and desire to have protected by Letters Patent will be pointed out in the appended claims.

What I claim as my invention is:

l. lIn an automatic telephone system, a pluraljity of classes of calling and called subscriberss lines, means for interconnecting said lines, ringing means in said connecting means, a ring control relay, circuit means for operating said relay in one manner dependent upon the class of said called subscribers line in case the calling line is ..70 of a particular class, said ringing means controlled by the operation of said relay in said one manner to ring said called subscriber in a pre- .ld'etermined manner, additional circuit means for operating said relay in a different manner in case 75.Isaid' calling line is of a diierent particular class 'called line 'having different potentials Ithereon, -a t ,relay in said connector switch connected Lto Aone of said ,contacts Vwh-ena lineis called, said relay operated, 'when the contact connected with vhas certain potential, to 'switch the ringing circuit fromsthe Vsaid-,nist ringing lead to the said second i' ringing lead to give an intermittent long ringing .signal to the called number.

3. In ran automatic telephone"s ystem, a plurality oi Aclasses of calling pand called subscribers lines, a plurality of 'connector switches common to all classes of subscriberslines, afconductorassociated with each said subscribers line, said 'lines and said conductors terminating on connectorswitch bank contacts 'for terminating calls, a

,relayin said connector switch controlled by'current over the said conductor of a particular called Iline for causing a specific type Lof rringing `signal to be given to said called :line 'in accordance with the .particular class to which said ycalled subscribers 'line `had Apreviously been assigned.

.4. lnvanautomatic telephone system, a plural- ,ity or" `classes .of subscribers lines, a conductor associated with `each saidsubscribers line, said .lines and said conductorsarranged in numerical A'order von banksoicontacts, a plurality of connecting switches .for `connecting i,with said lines and said conductors through the ,said banks of contacts, v-a pluraltyof .typesof ringing interrup- ,ter leads .attached ,to fsaid .contacts `ci .said conaductors in .any Vdesired manner, a relay `in each Aconnector switch .responsive to impulses V`oi current on said conductors to control the .type of ringing .signal to a called line,sad .typesroi interrup-ter leads `associated with the -said 4conductors foi' the said classes of `subscribers',lines giving the type ofinterrupted.ringingsignal which has Hpreviously been `assigned-,andassociated with ,said

called line.

`5. In f an .automatic telephone system, a 'pluralyity of classes foi subscriberslinesfeach with a-cor- 'responding lring :icontrol'conducton .said lines 4and said .conductors :arranged -in ,numerical order "on the contacts .of `automatic rswitch banks, :a -plurality o connector switches for rconnecting Kwith said "lines and said conductors by 'access to said ybank contacts, a pluralityoffringing interrupters `connected vat will to saidban'kfcontacts over :said conductors, a relay 'in each connector 4switch .re-

sponsive tolone oflsaidinterruptersicr controlling I the ringing signalto `a calledline Tin accordance with the type of ringing signal'rwhic'h has `been previously selected Irvand `assigned lto said :called line as determined by `the `interrupter connected therewith, meansin said connector switchcon'- rtrclled from a particular class l(if lsaid calling subscribers line for rendering ineffective 'the lcontrol lof the ringing rsignal from lthe'bank lcontactof the called line and ygiving to said `called '"line a 'different type of ringing signal. 5

`15. finan automaticftelephone :a plurality of classes Voi calling and'called subscribers" ilines, Ka `)plurality of connecting switches vwith `.means ifor 'intercoxmecting saidcallingfandr called subscribers linea said switches jincluding 'a relay responsive tocontrol from either the Jcalling or ycalled subscribers r"line for determining the ltype fof ringing signal tobe given, la pick-up-.rlay in each connecting switch operated when certain types of ringing -signalls are given *for `preventing lth'e ringing signal being given Ito 'the called line aprior to fthe commencement `fof `a complete fcode ringing signal.

VI ."-I-n an automatic :telephone system, "a *pluralfity -o'f classes of subscribers lines, n. yplurality 0I lconnecting means, a plurality of fof :ringing signals, vsaid connecting means @including :a irelajy responsive -tocontrl1from y.the terminal `)facilities ci *the calling or the #called fszibscribers line 'to determine the "ty'pe L'di ringing signal lto be randuincludingfa pick-up'relayfto prevent the ringing signal `"from"being@sent :.priortothe commence- 'fment fof a complete lring-ing signal and means 1whereby-vsaid-first"relay,in response toa call'ffrom fa yparticular class of ,'subscriber, rwill operate to render iineifective 'the zpick-ujn zrelay and apply ne. speci-'fic Itypecif =ringing signal to thecalled line.

8. In anautomatictelephcme system,-a plurality of classes of subscribers lines each with a corresponding ring -control conductor, "e plurality foi connecting Aswitches lfor interconnecting said 'li-nes, said switches lavailable `vfcriusefby :all l'classes `of subscribers lines, a `Aplurality-cf 1'types of uwring- "ing signals, means iin said `coi'xnecting switches responsive Ato scontro'l over said fring control Jconlductor of fonefclass for subscribers line for 'f'deter- 'mining the ltype of ringing "signal -tobe ugiven A4and this-same means effective When'the Fccllling'line Afis of said particular class land Awhen :the `y*called line fis engaged for 'Y preventing Ythe application of said ringing signal to the called line andfor `causing the transmission of unwanted n,signal ttc salidbusy "line.

-' '9. In f an l automatic "telephone system,a plurality of classes -`of subscribers 'lines 'each with a Vcorresponding :ring Icontrol conductor, ya plurality of `connecting `switches or "interconnecting :said

lines, said switches available yforfuse iby all classes a called `line, afsecond Ameansl said first means effective when the called line `is iengaged *for 'causing said secondm-eans -to *transmit-eWanted signal to 1said -engagedfline l0. :Inan-automatic^telephonesystem, aplurality of classes of subscribers lines each Y-iw'ith sa, corresponding ringfccntrolJ conductor, a plurality a. `of connecting switches 'ffor tinterconnecting lsaid subscribers lines, fla plurality Aof ringing signals,

said connecting `switches 'available for use 'by all classes of subscribersllines and includingmeans responsive 'to the control over fsaid ring -control conductors of either the calling -or called line =fcr ldetermining Vthe lftype of ringing ysignal `to be vvgiven to ra ycalled line said -means responsive to "calls ircm'a specic-wclassfof sbscriber'sfline lor rendering 'ine'ective the Acontrol fo'f said means -i'lmver the'fringfcontmlmonductnrtofisaidcalledflinm analice means effective when the called line is engaged `for 'applying a wanted signal to said called engaged line, and means whereby said specic class of calling subscriber may remain connected to the called busy line until said line is freed and means rresponsive to thev freeing of the said called line for disconnecting the wanted signal and giving immediately a predetermined type of ringing l1. In an automatic telephone system, a plurality of classes of subscribers lines, a busy signal,

a wanted signal, a plurality of switches for interconnecting said calling and called lines, a relay in each of said switches, a shunt circuit around said relay normally rendering said relay inoperative,.means for opening said shunt circuit only `in case the calling line in an interconnection is of a particular class, means for operating said relay after its shunt circuit is opened in response -to a busy connection to a called subscribers line,

said last means including a busy test means operative for connecting said busy signal to the ,calling line, a circuit for connecting said wanted `signal to the called line completed in'responseto` ,Y the operation of said relay, means for releasing said relay in response to the called line being freed, and means operative responsive to the release of said relay for connecting said calling line `to said Ireedcalled line.

12. In an automatic telephone system, a plurrality of classes of subscribers lines, a plurality .of connecting switches for the common use of all classes of subscribers for interconnecting said ;subscribers lines, a plurality of types of ringing ,calling line and for operating the said camping relay in case .said preferred service relay is operated to-cause the said wanted signal to be given to the said called busy line, means for rst causing the said busy relay to release after the said called busy line is freed after which the said 4camping relay releases to .cause the said wiper control relay to operate to connect the said calling 'line to the said called line and to connect said one type of said ringing signal thereto.

13. In an automatic telephone system, a conlnector switch for the interconnecting of a plurality of classes of subscribers' lines, a busy signal,

., a wanted signal, said connector including a busy frelay, a camping relay and a special relay, said 1 special relay responsive to calls from one class of =subscribers line and effective for operating saidf camping relay after operation of said busy relay for causing a wanted signal to be given to a called busy line, and means whereby said wanted signal Y means is rendered ineiective by the non-operation of said special relay when another said class of subscribers line calls a busy line and said other calling line will receive the busy signal in response to the operation of saidbusy relay.

14. In anvautomatic telephone system, a plul rality of connector switches for the common use of all classes of subscribers lines, a busy signal. a wanted signal, each of said connector switches including a wiper control relay, a busy relay, a

. camping relay and a relay responsive to calls v from'one class of said subscribers line to causo said wanted'signal to be given to a called busy line, means eiective when the said called line is busy whereby the said camping relay will be connected in series with the said busy relay, said camping relay then operating to connect the said wanted signal to the said busy called line, the said busy relay being the first to release when the said busy called line becomes free after which said camping relay releases to cause the said wiper control relay to connect said calling line with said called line.

15. In an automatic telephone system, a plurality of classes of subscribers lines, automatic switches for extending connections from one of the lines to another, a busy-relay, a wanted tone relay and a switching through relay, a class relay operated in response to a call from one class of subscribers line for connecting the wanted tone relay in series with the busy relay, said last two relays operated when a seized called line is busy toy'connect a busy tone to the calling subscrib- Lers line and a wanted tone to the called subscribers line, means responsive to the freeing of controlled by the release of said last relay to cause the operation of the switching through relay to connect the calling line to the called line.

16. In an automatic telephone system, a connector switch for the common use of all classes of subscribers lines, a busy signal, a wanted signal, said connectors including a busy relay, a wiper control relay, a camping relay and a class relay responsive to control over either the calling or called subscribers line, said class relay eilective when calling subscribers line is of one class and called line is busy for causing said busy relay and said camping relay to operate in series to connect said wanted signal to said called busy line and for causing the operated connector switch to camp on the said called busy line until said line is freed after which said wiper control relay is operated to make connection between said calling and called lines, said class relay effective when said calling line is of another class to shunt the said camping relayand render it inoperative and connect said busy signal to said calling subscriber.

17. In an automatic telephone system, a connector switch for the common use of a plurality of classes of subscribers lines, a busy signal, a wanted signal, said connector including a busy relay, a camping relay and a relay responsive only to calls from one class of said subscribers lines for causing the operation of said camping relay to cause said wanted signal to be given to a called busy line, means effective when the called line is busy whereby the said busy relay and said camping relay will operate in multiple to cause said wanted signal to be given to the said called busy line, means for preventingthe wanted signal from being given to unwantedv lines, and means whereby the said calling line will camp on the said called line and will be automatically conl'iected therewith when said called line is freed.

18. In an automatic telephone system, a plurality of classes of subscribers lines, means including connecting switches for interconnecting said lines, a plurality of ringing signals whereby said subscribers may be signalled by a series of intermittent short or intermittent long rings, said connecting switches including a shaft having a vertical motion, sets of contact springs actuated by said shaft when said shaft is moved vertically,

means whereby one set of springs will be actuated 13 when the shaft is moved vertically certain numbers of steps, means whereby another set of spring contacts will be actuated when said shaft is moved vertically diiierent numbers of steps to cause specic types of ringing signals to be given to the called line whose terminals are associated with the respective steps.

19. In an automatic telephone system, a plurality of classes of subscribers lines, each with a corresponding ring control conductor, means including connecting switches for interconnecting said lines, a plurality of ringing signals whereby said subscribers may be signaled by a series of intermittent short or intermittent long rings or a continuous ring, a relay in said connector switch responsive to current on the said ring control conductor of one class of subscribers line, said connecting switch including a shaft having a vertical rnotion, sets of contact springs actuated by said shaft when shaft is moved vertically, means whereby one set of springs will be actuated when said shaft is moved vertically certain numbers of steps, means whereby another set of spring contacts will be actuated when said shaft is moved vertically different numbers of steps to cause specific types of ringing signals to be given to the called line whose terminals are associated with the respective steps, said relay operated from the said ring control conductor of said one class of subscribers line to render the said shaft spring means ineffective and to give a different type of ringing signal to said called line.

20. In an automatic telephone system, a plurality of classes of subscribers lines, a plurality of connector switches for interconnecting said lines, said lines arranged in numerical order on the bank contacts of said switches, a ring control bank contact associated with each said subscribers set of line bank contacts, a relay in said connector, said relay operated when the said ring control contact of said called line is supplied with current for switching from one type of ringing signal to another type of ringing signal 21. In an automatic telephone system, a con nector switch with means for interconnecting a plurality of classes of calling and called subscribers lines, a pick-up lead supplied with intermittent current, a relay in said connecting means responsive to control from either the calling or called line in accordance with the class of line, a second or pick-up relay in said connecting means responsive to control from said pick-up lead, means in said connector switch effective only when calling line is of one class for causing the said pick-up relay to operate to prevent a partial code or ringing signal from reaching the called line.

22. In an automatic telephone system, a connector switch with means for interconnecting a plurality of classes of calling and called lines each with a corresponding ring control conductor, a pick-up lead supplied with intermittent current, a relay in said connecting meaim responsive to current from the said ring control conductor of either the said calling or called line, a second or pick-up relay in said connecting means responsive to current on said pick-up lead, means in said connector switch effective when said calling line is of a particular class to cause the said pick-up lead to be ineiective and to prevent the operation of the pick-up relay and to give a different type of ringing signal.

23. In a telephone system, a plurality of classes of subscribers lines, each with a corresponding ring control conductor and an individual trunk selecting switch, a plurality of connecting switches, means for directively controlling one of said connecting switches over one of said lines to select and connect with another one of said lines, a double wound relay in said switch for controlling the type of ringing signal to be sent to said selected line, means in said connecting switch or operating said relay through one of its windings frcm current on said ring control conductor of one class of said subscribers line through its said individual trunk selecting switch to give a continuous ringing signal to said called line, and means for controlling said relay over the other winding when another class of subscribers line seizes the connector switch.

24. In an automatic telephone system, a plurality of classes of subscribers lines, a plurality of connecting switches, a plurality of types of interrupter leads associated with the said subscribers lines, means for directively -controlling one of said connecting switches over one of said lines to select and connect with another one of said lines, a double wound relay in said connecting switch for controlling the type of ringing signal to be sent to a selected called line, means in said switch for operating said relay through one of its windings from interrupted current on said interrupted lead associated with the said selected called line to give a ringing signal in accordance with the type of signal previously chosen and assigned to said selected line, and means for controlling said relay over the other winding when a specific class of subscribers line seizes the connector for rendering ineffective the control from the interrupter lead associated with the called line and to give a specific type of ringing signal.

25. In an automatic telephone system, a plurality of classes of subscribers lines, a busy signal, a wanted signal, an automatic switch for interconnecting said calling and called lines, a busy relay and an auxiliary busy relay in said switch, means for operating said switch from a calling line to extend a connection to a called line, means for operating said busy relay alone in response to the extension of a call to a busy called line in case said calling line is of a particular class, a locking circuit for said busy relay completed independent of the called line, a circuit completed by said busy relay for connecting said busy signal to the calling line, means for operating said auxiliary relay in series with said busy relay in response to the extension of a call to a busy called line in case the calling line is of a different class, a circuit completed by said auxiliary busy relay for connecting said wanted signal to the called line, and a locking circuit for said busy auxiliary relay completed by the operation of said auxiliary busy relay dependent upon the busy condition of said called line.

CLARENCE E. LOMAX.

REFERENCES CITED The following references are of record in the 5 file of this patent:

UNITED STATES PATENTS Number Name Date 1,278,330 Goodrum Sept. 10, 1918 1,459,860 Powell June 26, 1923 1,514,837 Deakin Nov. 1l, 1924 1,556,751 Benson Oct. 12, 1925 1,685,547 Lomax Sept. 25, 1928 1,763,157 King June 10, 1930 1,925,681 Uda Sept. 5, 1933 

